Chanokporn Saeung และ Tharapong Vitidsant. (2009) Preparation of activated carbon from petrochemical waste sludge by chemical and physical activation. Chulalongkorn University:ม.ป.ท.Chanokporn Saeung และ Tharapong Vitidsant. 2009. Preparation of activated carbon from petrochemical waste sludge by chemical and physical activation. ม.ป.ท.:Chulalongkorn University;Chanokporn Saeung และ Tharapong Vitidsant. Preparation of activated carbon from petrochemical waste sludge by chemical and physical activation. ม.ป.ท.:Chulalongkorn University, 2009. Print.